飞来峡流域基于栅格DEM的分布式水文模拟

Grid DEM-based distributed hydrological modeling for Feilaixia watershed

基于栅格DEM的分布式水文模型能利用DEM提供的流域地形,包括流域边界、坡度、坡向、河网等特征信息,充分考虑下垫面条件的不均匀性及空间尺度相耦合性.以集水面积34097km2的飞来峡水库流域为例,利用SRTM90m精度的DEM资料提取流域特征信息和划分水系和子流域,采用基于栅格DEM的分布式水文模型来计算每个栅格的产汇流,河道汇流采用马斯京根法,参数率定采用SCE-UA优化算法.结果表明:一个结构简单、物理过程明确、参数较少的栅格DEM分布式模型可以被用于大中型流域的水文模拟,以更好地利用流域地形特征信息和描述流域水文过程.

A grid digital elevation model （DEM）-based distributed watershed hydrological model which can utilize the watershed terrain characteristics represented by DEM, and take into account the asymmetry and the spatial scale coupling of the underlying surface, has become a hotspot in current hydrological model re- search. Taking Feilaixia reservoir basin with a catchment area of 34 097 km2 for example, the SRTM 90 m DEM data are used for extracting terrain characteristics information and delineating drainage networks and subwatershed; and a grid DEM-based distributed hydrological model is used to calculate the runoff in each DEM grid. Muskingum model is applied to channel flow routing and SCE-UA optimization algorithm is employed for parameters calibration and validation. It is shown that a grid DEM-based distributed hydro- logical model with simple structure, physical process and less parameters can be used to modeling the hydrological processes in the basin so as to achieve the better use of watershed terrain characteristics infor- mation and hydrological processes understanding.